The team is guarding against a setback with Escobar, who has dealt with a sore shoulder for about a week. He is 1 for 6 in spring games with the Royals.
Kuroda, who isn't facing batters in Monday's bullpen session, was roughed up in his last spring start, giving up six runs in 3 2/3 innings and raising his spring ERA from 0.00 to 6.48.
Lackey (1-0) kept St. Louis off the scoreboard for two innings before Daniel Descalso doubled home a pair of runs in the second inning. The Cardinals added three more runs in the third on a two-run double from Pete Kozma and an RBI single from Kolten Wong.
Lackey has a 9.39 ERA through two spring starts.
Miller retired the side in order and escaped the second inning without giving up a run despite issuing two walks. However, the Red Sox finally got on the board in the third inning with a two-run homer by Dustin Pedroia. The final run charged to Miller came in the fourth inning as Tyler Lyons balked home one of his inherited runners.
Miller has a 6.23 ERA through three spring starts. He's allowed a home run in each start, while striking out nine batters and issuing three walks.
"Felt little more adrenaline today," Motte said. "I felt more intensity than last time. It's starting to feel a little more normal doing it.
"I'm thinking I know I can throw this and it's not going to fall off. It's in there where it should be. It's doing what it should do. I think last time I was a little tentative, a little hesitant.... Last time was already a big step. The hitters are swinging. It doesn't matter if minor league guys or big league guys, if they get a good pitch they're going to put a good swing on it."